To know the proper functioning of al the available options in ur sony erricson mobile, just follow tho steps given bellow

1)press the right navigation key once

2)press *

3)press left navigation key twice

4) press*

5)press left navigation key once and

6)press *

after tis u wil get a variety of options like

i)service info

ii)service settings

iii)service tests

iv)text labels

make use of these options to test the ability of ur mobile...

tis trick will b very usefull for those who buy mobilles in second hand